Viola Davis, King Hedley II Tony-nominated for August Wilson's Seven Guitars, the related play that served as "prequel" to King Hedley II, Davis has a solid reputation for plunging into her characters. Her credits include Everybody's Ruby and God's Heart, among others, but King Hedley II (in which she plays the title character's woman) may be earning her the best reviews of her career.

Viola Davis, King Hedley II Tony-nominated for August Wilson's Seven Guitars, the related play that served as "prequel" to King Hedley II, Davis has a solid reputation for plunging into her characters. Her credits include Everybody's Ruby and God's Heart, among others, but King Hedley II (in which she plays the title character's woman) may be earning her the best reviews of her career.

Johanna Day, Proof Solid Off-Broadway credits such as Three Tall Women, How I Learned to Drive, The Country Club and Vick's Boy came before her role as Claire, older sister to Mary Louise-Parker's troubled character in Proof. At turns funny and frustrated and sophisticated, Day's Claire comes off not as a villain (which is how a lesser actress would play it) but as a sibling pained about the fact that she does not speak the same language as her sister and father.

Penny Fuller, The Dinner Party Shifting freely between musicals and plays over the years, Fuller was Tony-nominated for playing evil Eve Harrington in Applause, and she also appeared in Richard Rodgers' Rex, William Finn's A New Brain, Wendy Wasserstein's An American Daughter and Jeffrey Hatcher's Three Viewings. In the new dark comedy by Neil Simon, she bites into the role of Gabriella with great zest (she's the one who throws the party, after all), and Simon's writing allows her to be the one we care about most at play's end.

Marthe Keller, Judgment at Nuremberg Keller, playing Madame Bertholt, a German woman who strikes up a relationship with the American judge who stays with her, was last seen on the American stage at Carnegie Hall in Jeanne Au Bucher. Her other stage credits include A Day in the Death of Joe Egg, The Three Sisters, Betrayal, La Ronde, Hamlet and T.H. Lawrence (with Ben Kingsley). Films include "Marathon Man," "Black Sunday" and "Bobby Deerfield."

Michele Lee,The Tale of the Allergist's Wife Although Lee was seen on Broadway in How to Succeed in Business... in the 1960s and Seesaw (for which she earned a Tony nomination) in the 1970s, she became widely known for her sympathetic role as Karen on TV's soaper, "Knots Landing." Broadway audiences are now surprised and titillated by her sexy, aggressive and somewhat menacing performance as "Lee," a childhood friend of Linda Lavin's character in the new Charles Busch comedy. Analysis: Viola Davis is the favorite to win in this category for the sheer emotional muscularity of her performance, although Keller and Day provide unique support to their plays. Lee and Fuller will likely be overlooked, partly (and unfairly) because they are in plays that are considered less serious-minded.